Online and other electronic advertising allows advertisers to display advertisements (or ads) to end users, including those who are potential customers. For example, a webpage can include one or more opportunities for inserting advertisements (e.g., space for a banner advertisement across the top of the webpage, spaces for advertisements along the sides of the webpage, overlays, etc.). When a user device (e.g., a computer running a web browser) processes a webpage for display, the user device can request an advertisement for one of the advertising opportunities on the webpage from an advertising server (or ad server). The ad server can select an advertisement for display within the area of the webpage associated with the advertising opportunity. For example, the ad server can select, based on declarative rules set by the publisher, a banner ad from a particular advertiser from a set of multiple banner ads from multiple advertisers for display to the user in the banner ad space of the webpage. Each presentation of an advertisement within a webpage can be referred to as an impression.
Ad networks have been developed to enable advertisers to find available advertising opportunities (e.g., spaces on webpages in which to display their ads) and to provide publishers a way to find ads to be displayed on their webpages. For example, a publisher can use a realtime bidding platform to sell an impression to an advertiser (e.g., the winning bidder advertiser can provide the advertisement that will be displayed to a user). When a user device processes a webpage for display, the web browser can request an advertisement for one of the impression opportunities on the webpage. In response to this request, the realtime bidding platform can request bids from advertisers for the impression opportunity. The realtime bidding platform can collect bids from competing advertisers and select the advertiser having the highest bid. The publisher, or one of its ad servers, can then provide to the user an ad from the advertiser having the highest bid. In some applications, advertisers can provide advertising data (e.g., data that indicates which ads on a publisher's webpage the advertiser wishes to buy) to user devices for storage. However, some publishers want to control storing of advertisement data associated with the publisher's webpages. Accordingly, there is a need for providing publishers greater control over how advertisement data is stored on user devices, such as controlling the domain with which advertisement data is associated.